A number of environment variables can be used to configure the behavior of the library. There are also functions to configure this behavior in code. The environment variables are convenient when troubleshooting problems.
Endpoint Overrides
GOOGLE_CLOUD_CPP_CONFIG_ENDPOINT=... overrides the EndpointOption (which defaults to "config.googleapis.com") used by MakeConfigConnection().
GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc: turns on tracing for most gRPC calls. The library injects an additional Stub decorator that prints each gRPC request and response. Unless you have configured your own logging backend, you should also set GOOGLE_CLOUD_CPP_ENABLE_CLOG to produce any output on the program's console.
See Also
google::cloud::LoggingComponentsOptionGOOGLE_CLOUD_CPP_TRACING_OPTIONS=...: modifies the behavior of gRPC tracing, including whether messages will be output on multiple lines, or whether string/bytes fields will be truncated.
See Also
google::cloud::GrpcTracingOptionsOptionGOOGLE_CLOUD_CPP_ENABLE_CLOG=yes: turns on logging in the library, basically the library always "logs" but the logging infrastructure has no backend to actually print anything until the application sets a backend or they set this environment variable.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-04-17 UTC."],[[["This document provides a comprehensive list of configuration options and environment variables for the C++ client library, ranging from versions 2.16.0 to the release candidate 2.37.0-rc."],["Environment variables can be used to configure the library's behavior, which is particularly useful for troubleshooting, such as overriding the default endpoint with `GOOGLE_CLOUD_CPP_CONFIG_ENDPOINT`."],["Tracing for gRPC calls can be enabled via the `GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc` environment variable, allowing detailed logging of each request and response."],["The `GOOGLE_CLOUD_CPP_ENABLE_CLOG=yes` environment variable activates the logging functionality in the library, ensuring that log messages are outputted to the console when used with the tracing variable."],["While `GOOGLE_CLOUD_PROJECT` can be set for examples and tests, it has no impact on the library's functionality, and only modifies how the application interacts with a project."]]],[]]